exam 1: CH3

Question 1

the 2000-2004 drought in cali dramatically shortened the growing season, what was the consequence of this for the mustard plant, Brassica rapa?

Answer 1

natural selection led to earlier flowering time in the plants

Question 2

natural selection acts on ____ differences in a pop

Answer 2

phenotypic

Question 3

natural selection requires that variation exists in a population and the variation is ____

Answer 3

heritable

Question 4

for traits to evolve by natural selection, individuals must experience differetial productive success. this means that ___

Answer 4

individuals w/ certain traits are more sucessful than the others in the pop surviving and reproducing

Question 5

variation is generated in a pop primarily by

Answer 5

mutations

Question 6

all of the following are types of traits that evolutionary biologists might study in regard to natural selection EXCEPT

Answer 6

traits acquired during the lifetime of an organism

Question 7

spines, flowers, and a waxy stem coating are all adaptations of cacti because ___

Answer 7

these traits increase the fitness of cacti & arose as a result of natural selection for their current function

Question 8

the exquisite complexity of traitd such as the vertebrate eye seems to pose a problem for evolution by natural selection. How do evolutionary biologists think complex eyes evolved?

Answer 8

eyes evolved in gradual steps. each of which was fully functional and adaptive in improving visual acuity

Question 9

a trait that serves one purpose today but evolved under different selective conditions and previously had a different function

Answer 9

exaptation

Question 10

considering the phylogenetic evidence of feather evolution, all of the following might have been original functions of feathers EXCEPt

Answer 10

flight

Question 11

lens crystallins form the transparent lens of the eye. in guinea pigs, lens crystallins also function as alcohol dehydrogenase. What is this an example of

Answer 11

gene sharing

Question 12

evolutionary change in one species that affects the selective conditions for a second species is known as which of the following

Answer 12

coevolution

Question 13

what is the term for a simultaneous action of natural selection on each side of host-pathogen interaction?

Answer 13

an evolutionary arms race

Question 14

one constraint on what natural selection can achieve comes from the fact that it lacks foresight. This means that

Answer 14

selection favors changes that are immediately beneficial, not changes that may be useful sometime in the future